Ok I figured it out

This:
Code
{$config.BASE_URL}/images/{$style_array.general}/newpm.gif


equals this:

Code
http://www.yourdomain.com/forums/images/general/default/newpm.gif


Now this is assuming your style is the default board style. If you are using a style with it's own image folder such as "beagleworld" then "default" would be "beagleworld".